/Engine/Source/Editor/UnrealEd/Classes/Commandlets/ResavePackagesCommandlet.h
Allow the commandlet to perform any operations on the export/import table of the package before all objects in the package are loaded.
virtual void PerformPreloadOperations ( [FLinkerLoad](API\Runtime\CoreUObject\UObject\FLinkerLoad) * PackageLinker, bool & bSavePackage )